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891.
Michael M. Roy Michael J. Liersch Stephen Broomell 《Organizational behavior and human decision processes》2013
People have been shown to view their beliefs as being prototypical (modal) but their abilities as (falsely) unique (above or below average). It is possible that these two viewpoints – self as prototypical and self as unique – can be reconciled. If the distribution of ability for a given skill is skewed such that many others have high (low) ability and few others have low (high) ability, it is possible that a majority of peoples’ self-assessments can be above (below) average. Participants in 5 studies demonstrated an understanding that various skills have skewed ability distributions and their self-assessments were related to distribution shape: high when negatively skewed and low when positively skewed. Further, participants tended to place themselves near the mode of their perceived skill distribution. Participants were most likely to think that they were good at skills for which they thought that most others were also good. 相似文献
892.
Gaston Godin Ariane Bélanger-Gravel Lydi-Anne Vézina-Im Steve Amireault Andrea Bilodeau 《Psychology & health》2013,28(9):1086-1099
Objective: This study investigated the question–behaviour effect of measuring intention in the interrogative or declarative form combined or not with a measure of moral norm. Design: A sample of 762 participants was randomised according to a 2?×?2 factorial design. Main outcome measures: Cognitions were assessed at the baseline, and physical activity behaviour was self-reported three weeks later. Results: At baseline, there were no significant differences on the studied variables. An ANOVA showed a significant interaction effect between the two experimental conditions (p?=?0.04). Post-hoc contrast analyses showed that the interrogative intention-only condition significantly differed from the declarative intention-only (d?=?0.21, p?=?0.03) and interrogative intention?+?moral norm (d?=?0.22, p?=?0.03) conditions. Conclusion: Results suggest that self-posed questions about a future action increases the likelihood of doing it when these questions are not accompanied by measures of moral norm. This provides support for using introspective self-talk to favour the adoption of behaviour. 相似文献
893.
Most theories of motivation and behavior (and lay intuitions alike) consider pain and effort to be deterrents. In contrast to this widely held view, we provide evidence that the prospect of enduring pain and exerting effort for a prosocial cause can promote contributions to the cause. Specifically, we show that willingness to contribute to a charitable or collective cause increases when the contribution process is expected to be painful and effortful rather than easy and enjoyable. Across five experiments, we document this “martyrdom effect,” show that the observed patterns defy standard economic and psychological accounts, and identify a mediator and moderator of the effect. Experiment 1 showed that people are willing to donate more to charity when they anticipate having to suffer to raise money. Experiment 2 extended these findings to a non‐charity laboratory context that involved real money and actual pain. Experiment 3 demonstrated that the martyrdom effect is not the result of an attribute substitution strategy (whereby people use the amount of pain and effort involved in fundraising to determine donation worthiness). Experiment 4 showed that perceptions of meaningfulness partially mediate the martyrdom effect. Finally, Experiment 5 demonstrated that the nature of the prosocial cause moderates the martyrdom effect: the effect is strongest for causes associated with human suffering. We propose that anticipated pain and effort lead people to ascribe greater meaning to their contributions and to the experience of contributing, thereby motivating higher prosocial contributions. We conclude by considering some implications of this puzzling phenomenon. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
894.
D.J. Dunstan A.J. Thomas I. de Lavau J.J. Jardin A.J. Bushby 《Philosophical Magazine Letters》2013,93(7):308-313
Experimental tests of strain-gradient plasticity theory rely on studies of the size effect (smaller is stronger) in micromechanical testing. The plastic strain gradient is varied by varying the size of the specimen. This confounds the direct effects of the size and the effects of the strain gradient. We propose experiments on foil sandwich structures in which these parameters are separated. Preliminary results suggest that it is the foil thickness that determines the strength, not the strain gradient. 相似文献
895.
A novel, instrumented microindentation technique was successfully used to measure the temperature associated with the martensitic transformation leading to the recovery of plastic strain in a Nickel–Titanium (NiTi) shape memory alloy. Following a standard indentation cycle, the indenter was partially unloaded such that a good contact was maintained between indenter and specimen surface. The onset and finish temperature of the martensitic transformation, the associated volume contraction, and the amount of the recovered plastic deformation were determined by quantifying the indenter displacement as a function of temperature. These experiments were compared to conventional measurements of the transformation temperature by differential scanning calorimetry and compression testing. 相似文献
896.
Guo-Dong Zhan Joshua D. Kuntz Hsin Wang Chong-Min Wang Amiya K. Mukherjee ∥ 《Philosophical Magazine Letters》2013,93(7):419-423
Dense single-wall-carbon-nanotube-(SWCNT)-reinforced alumina nanocomposites have been fabricated by a novel spark-plasma-sintering technique. Anisotropic thermal properties have been found in carbon nanotube composites. The introduction of ropes of SWCNTs gives rise to a decrease in the transverse thermal diffusivity with increasing carbon nanotube content while it does not change the in-plane thermal diffusivity. This is scientifically interesting and technologically important for the development of materials for novel thermal barrier coatings. 相似文献
897.
P. Grassia 《Philosophical Magazine Letters》2013,93(6):403-409
A model of the structure of two-dimensional foam (cells separated by circular arcs (films) meeting at threefold vertices) is considered. Films that are so curved as to be nearly semicircular arcs are problematic for conventional foam structure computations, which aim to identify the pressures needed to achieve specified bubble areas. When the films have near semicircularity, tiny variations in pressure can lead to large changes in the computed bubble area, and hence a failure to meet the specified targets. A new algorithm for determining foam structure is presented. It is based on 'freezing' most of the system, except the nearly semicircular arcs, and then finding the particular bubble pressures associated with the latter via an analytic approximation. This procedure is shown to work well for structure relaxation in a small bubble cluster. Large relaxed bubble clusters are considered briefly at the end of the paper. 相似文献
898.
{111} stacking faults and nanotwins in epitaxial BaTiO3 thin films on MgO substrates have been investigated by high-resolution transmission electron microscopy. In many cases, the stacking faults and nanotwins were found to be accompanied by partial dislocations. These partial dislocations can be classified as two different types, analogous to the situation in the fcc structure. One is of the Shockley type with the Burgers vector (a/3)<112>. The other is of the Frank type with the Burgers vector (a/3)<111>. The movements of both types of partial can lead to the {111} stacking faults and the {111} twins observed in these films. 相似文献
899.
The nucleation of voids at the initial stage of hollow nanoshell formation is described in terms of the thermodynamics of nucleation in systems of finite size (or small systems) pumped with vacancies by interdiffusion-driven vacancy influx. Crossovers from suppressed nucleation to metastable nucleus formation and then to stable nucleus formation are analysed, describing, in particular, the possibility of significant supersaturations with vacancies of the metallic core. It is shown that at higher temperatures it becomes more favourable to nucleate at once a large single void instead of multiple tiny voids. 相似文献
900.
An inverse “smaller is stronger” trend is predicted on the basis of molecular dynamics simulations of α-titanium (Ti) single-crystal nanopillars orientated for double prismatic slips when the nanopillars are less than 7?nm wide. This trend is attributed to a significant increase in the surface energy due to the nucleation and propagation of edge dislocations on the surface of the pillars. 相似文献